The Loop is PHP code used by WordPress to display posts. Using The Loop, WordPress processes each post to be displayed on the current page, and formats it according to how it matches specified criteria within The Loop tags. Any HTML or PHP code in the Loop will be processed on each post.

When WordPress documentation says "This tag must be within The Loop", such as for specific Template Tags or plugins, the tag will be repeated for each post. For example, The Loop displays the following information by default for each post:

You can display other information about each post using the appropriate Template Tags or (for advanced users) by accessing the $post variable, which is set with the current post's information while The Loop is running.

Using the Loop

The Loop should be placed in index.php and in any other Templates used to display post information.

Be sure to include the call for the header template at the top of your Theme's templates. If you are using The Loop inside your own design (and your own design is not a template), set WP_USE_THEMES to false:

Loop Examples

Style Posts From Some Category Differently

This example displays each post with its Title (which is used as a link to the Post's Permalink), Categories, and Content. It also allows posts in a category with Category ID '3' to be styled differently. To accomplish this, the in_category()Template Tag is used. Read the comments carefully to see what each part of the code is doing.

Note: All HTML code must be outside the <?php ?> tags. And, PHP code (even things as simple as curly braces: } ) must be inside the <?php ?> tags. You can start and stop blocks of PHP code to intersperse HTML code within if and else statements, as shown in the above example.

Exclude Posts From Some Category

This example demonstrates how to hide a specific Category or Categories from being displayed. In this case, posts from Categories 3 and 8 are excluded. The example is different than the example above in that it makes a change to the query itself.

Note: If you use this example for your main page, you should use a different Template for your Category archives; otherwise, WordPress will exclude all posts in Category 3 and Category 8, even when viewing that Category Archive! However, if you want to use the same template file, you can avoid this by using the is_home() tag to ensure that posts from Category 3 and Category 8 will only be excluded from the main page:

There are other Conditional Tags that can be used to control the output depending on whether or not a particular condition is true with respect to the requested page.

Multiple Loops

This section deals with advanced use of The Loop. It's a bit technical, but don’t let that scare you. We’ll start with an easy example and work up from there. With a little common sense, patience, and enthusiasm, you too can do multiple loops.

First off, why would one want to use multiple loops? In general, the answer is that you might want to do something with one group of posts, and do something different to another group of posts, but display both groups on the same page. "Something" could mean almost anything; you are only limited by your PHP skill and your imagination.

We will get into examples below, but first you should read about the basics. Take a look at the basic Loop. It consists of:

In English (PHP types and people familiar with code speak can skip to below), the above would be read: If we are going to be displaying posts, then get them, one at a time. For each post in the list, display it according to <!-- do stuff ... -->. When you hit the last post, stop. The do stuff line(s), are template dependent.

A little aside on Do stuff: in this example it is simply a placeholder for a bunch of code that determines how to format and display each post on a page. This code can change depending on how you want your WordPress to look. If you look at the Kubrick theme’s index.php the do stuff section would be everything below:

An explanation for the coders out there:
The have_posts() and the_post() are convenience wrappers around the global $wp_query object, which is where all of the action is. The $wp_query is called in the blog header and fed query arguments coming in through GET and PATH_INFO. The $wp_query takes the arguments and builds and executes a DB query that results in an array of posts. This array is stored in the object and also returned back to the blog header where it is stuffed into the global $posts array (for backward compatibility with old post loops).

Once WordPress has finished loading the blog header and is descending into the template, we arrive at our post Loop. The have_posts() simply calls into $wp_query->have_posts() which checks a loop counter to see if there are any posts left in the post array. And the_post() calls $wp_query->the_post() which advances the loop counter and sets up the global $post variable as well as all of the global post data. Once we have exhausted the loop, have_posts() will return false and we are done.

Loop Examples

Below are three examples of using multiple loops. The key to using multiple loops is that $wp_query can only be called once. In order to get around this it is possible to re-use the query by calling rewind_posts() or by creating a new query object. This is covered in example 1. In example 2, using a variable to store the results of a query is covered. Finally, ‘multiple loops in action’ brings a bunch of ideas together to document one way of using multiple loops to promote posts of a certain category on your blog’s homepage.

Multiple Loops Example 1

In order to loop through the same query a second time, call rewind_posts(). This will reset the loop counter and allow you to do another loop.

If you are finished with the posts in the original query, and you want to use a different query, you can reuse the $wp_query object by calling query_posts() and then looping back through. The query_posts() will perform a new query, build a new posts array, and reset the loop counter.

The query object my_query is used because you cannot use the global have_posts() and the_post() since they both use $wp_query. Instead, call into your new $my_query object.

Multiple Loops Example 2

Another version of using multiple Loops takes another tack for getting around the inability to use have_posts() and the_post(). To solve this, you need to store the original query in a variable, then re-assign it with the other Loop. This way, you can use all the standard functions that rely on all the globals.

Multiple Loops in Action

The best way to understand how to use multiple loops is to actually show an example of its use. Perhaps the most common use of multiple loops is to show two (or more) lists of posts on one page. This is often done when a webmaster wants to feature not only the very latest post written, but also posts from a certain category.

Leaving all formatting and CSS issues aside, let us assume we want to have two lists of posts. One which would list the most recent posts (the standard 10 posts most recently added), and another which would contain only one post from the category ‘featured’. Posts in the ‘featured’ category should be shown first, followed by the second listing of posts (the standard). The catch is that no post should appear in both categories.

Set $my_query equal to the result of querying all posts where the category is named featured and by the way, get me one post only. Also, set the variable $do_not_duplicate equal to the ID number of the single post returned. Recall that the Do stuff line represents all the formatting options associated for the post retrieved.

Note that we will need the value of $do_not_duplicate in the next step to ensure that the same post doesn't appear in both lists.

Step 2. The second loop, get the X latest posts (except one).

The following code gets X recent posts (as defined in WordPress preferences) save the one already displayed from the first loop and displays them according to Do stuff.

Get all posts, where a post equals $do_not_duplicate then just do nothing (continue), otherwise display all the other the posts according to Do stuff. Also, update the cache so the tagging and keyword plugins play nice. Recall, $do_not_duplicate variable contains the ID of the post already displayed.

The End Result

Here is what the final piece of code looks like without any formatting:

The end result would be a page with two lists. The first list contains only one post -- the most recent post from the 'feature' category. The second list will contain X recent posts (as defined in WordPress preferences) except the post that is already shown in the first list. So, once the feature post is replaced with a new one, the previous feature will show up in standard post list section below (depending on how many posts you choose to display and on the post frequency). This technique (or similar) has been used by many in conjunction with knowledge of the Template Hierarchy to create a different look for home.php and index.php. See associated resources at the bottom of this page.

Note for Multiple Posts in the First Category

If posts_per_page=2 or more, you will need to alter the code a bit. The variable $do_not_duplicate needs to be changed into an array as opposed to a single value. Otherwise, the first loop will finish and the variable $do_not_duplicate will equal only the id of the latest post. This will result in duplicated posts in the second loop. To fix the problem replace